KR940003083Y1 - High frequency tunning circuit - Google Patents
High frequency tunning circuit Download PDFInfo
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- KR940003083Y1 KR940003083Y1 KR2019910023751U KR910023751U KR940003083Y1 KR 940003083 Y1 KR940003083 Y1 KR 940003083Y1 KR 2019910023751 U KR2019910023751 U KR 2019910023751U KR 910023751 U KR910023751 U KR 910023751U KR 940003083 Y1 KR940003083 Y1 KR 940003083Y1
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03J—TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
- H03J3/00—Continuous tuning
- H03J3/02—Details
- H03J3/16—Tuning without displacement of reactive element, e.g. by varying permeability
- H03J3/18—Tuning without displacement of reactive element, e.g. by varying permeability by discharge tube or semiconductor device simulating variable reactance
- H03J3/185—Tuning without displacement of reactive element, e.g. by varying permeability by discharge tube or semiconductor device simulating variable reactance with varactors, i.e. voltage variable reactive diodes
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03J—TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
- H03J5/00—Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner
- H03J5/24—Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner with a number of separate pretuned tuning circuits or separate tuning elements selectively brought into circuit, e.g. for waveband selection or for television channel selection
- H03J5/242—Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner with a number of separate pretuned tuning circuits or separate tuning elements selectively brought into circuit, e.g. for waveband selection or for television channel selection used exclusively for band selection
- H03J5/244—Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner with a number of separate pretuned tuning circuits or separate tuning elements selectively brought into circuit, e.g. for waveband selection or for television channel selection used exclusively for band selection using electronic means
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N5/00—Details of television systems
- H04N5/44—Receiver circuitry for the reception of television signals according to analogue transmission standards
- H04N5/50—Tuning indicators; Automatic tuning control
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- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Signal Processing (AREA)
- Channel Selection Circuits, Automatic Tuning Circuits (AREA)
Abstract
내용 없음.No content.
Description
제1도는 종래의 고주파 동조회로를 보인 회로도.1 is a circuit diagram showing a conventional high frequency tuning circuit.
제2도는 슈퍼밴드의 방송신호 선택시 종래의 고주파 동조회로의 등가회로도.2 is an equivalent circuit diagram of a conventional high frequency tuning circuit when a broadcast signal of a super band is selected.
제3도는 VHF하이밴드의 방송신호 선택시 종래의 고주파 동조회로의 등가회로도.3 is an equivalent circuit diagram of a conventional high frequency tuning circuit in selecting a broadcast signal of a VHF high band.
제4도는 본 고안의 고주파 동조회로도.4 is a high frequency tuning circuit diagram of the present invention.
제5도는 종래 및 본 고안의 고주파 동조회로의 대역폭 특성곡선을 보인 그래프.5 is a graph showing a bandwidth characteristic curve of a high frequency tuning circuit of the prior art and the present invention.
* 도면의 주요부분에 대한 부호의 설명* Explanation of symbols for main parts of the drawings
11 : 하이밴드 동조부 12 : 로우밴드 동조부11 high band tuning section 12 low band tuning section
C19 : 콘덴서 D11-D14 : 다이오드C19: Capacitor D11-D14: Diode
HBV : 하이밴드 선택신호 L15,L16 : 코일HBV: High band selection signal L15, L16: Coil
LBV : 로우밴드 선택신호 TU : 튜닝전압LBV: Low band selection signal TU: Tuning voltage
본 고안은 비디오 카세트 레코더 및 텔레비젼 수상기등과 같은 기기에서 튜닝전압에 따라 가변용량 다이오드의 용량을 가변시켜 LC공진회로의 공진주파수를 가변시키면서 VHF밴드의 소정채널의 방송신호를 수신하는 VHF밴드 전자동조 튜너의 고주파 동조회로에 관한 것으로 VHF하이밴드 및 VHF로우밴드는 물론 CATV(Community Antenna TeleVision)채널인 슈퍼밴드를 포함하는 VHF의 전체 대역을 2밴드화로 광대역화를 이루고 방송신호를 정확히 수신할 수 있도록 하는 VHF밴드 전자동조 튜너의 고주파 동조회로에 관한 것이다.The present invention is a VHF band full-tuning for receiving broadcast signals of a predetermined channel of the VHF band while varying the resonant frequency of the LC resonance circuit by varying the capacitance of the variable capacitance diode according to the tuning voltage in equipment such as a video cassette recorder and a television receiver. A high-frequency tuning circuit of a tuner is provided to widen the entire band of the VHF including the VHF high band and the VHF low band as well as the super band which is the CATV (Community Antenna TeleVision) channel in two bands to receive broadcast signals accurately. A high frequency tuning circuit of a VHF band fully tuned tuner.
일반적으로 CATV 방송신호를 수신하는 채널인 슈퍼밴드를 포함하는 VHF밴드의 전자동조 튜너 즉, 수신대역이 40-470㎒인 전자동조 튜너는 반도체 소자의 특성 및 회로의 구성상 VHF로우밴드 VHF하이밴드 및 슈퍼밴드의 3개의 밴드로 구분해야 VHF대역의 모든 방송신호를 수신할 수 있도록 되어 있다.In general, the VHF band fully tuned tuner including a superband, which is a channel for receiving CATV broadcast signals, that is, the tuned tuner having a receive band of 40 to 470 MHz, is a VHF low band VHF high band due to the characteristics of a semiconductor device and a circuit configuration. And three bands of the super band to receive all the broadcast signals of the VHF band.
즉, 슈퍼밴드를 포함하여 VHF대역의 방송신호를 수신하는 종래의 전자동조 튜너는 제1도에 도시된 바와같이 안테나(ANT)의 수신신호에서 VHF대역의 방송신호를 통과시키고 방해파는 제거하는 필터(1)와, 상기 필터(1)의 출력신호를 증폭하는 증폭기(2)와, 상기 증폭기(2)의 출력신호에서 선택된 채널의 방송신호만을 혼합기로 출력하는 고주파 동조회로(3)로 구성된다.That is, the conventional fully tuned tuner that receives the broadcast signal of the VHF band including the superband is a filter for passing the broadcast signal of the VHF band from the received signal of the antenna ANT as shown in FIG. (1), an amplifier (2) for amplifying the output signal of the filter (1), and a high frequency tuning circuit (3) for outputting only the broadcast signal of the channel selected from the output signal of the amplifier (2) to the mixer. do.
고주파 동조회로(3)는, 증폭기(2)와 혼합기의 사이에 직렬로 연결되어 유도 결합되는 코일(L1,L2,L3,L6,L5,L4)과, 튜닝전압(TU)에 따라 용량이 가변되면서 콘덴서(C1)(C2) 및 코일(L1)(L4)과는 각기 슈퍼밴드의 방송신호에 공진되고 콘덴서(C1)(C2) 및 코일(L1,L2)(L4,L5)과는 각기 VHF하이밴드의 방송신호에 공진되며, 콘덴서(C1)(C2) 및 코일(L1-L3)(L4-L6)과는 각기 VHF로우밴드의 방송신호에 공진되게 하는 가변용량 다이오드(VD1)(VD2)와, 슈퍼밴드, VHF하이밴드 및 VHF로우밴드 선택신호(SB)(HB)(LB)에 따라 상기 코일(L1)(L4)과, 코일(L1,L2)(L3,L4)과, 코일(L1-L3)(L4-L6)이 각기 유도 결합되게 하는 다이오드(D1,D2)(D3,D4)(D5) 및 콘덴서(C3)(C4)(C5)로 구성하였다.The high frequency tuning circuit 3 has a capacitance depending on the tuning voltage TU and the coils L1, L2, L3, L6, L5, L4 connected in series between the amplifier 2 and the mixer. While variable, the capacitors C1, C2 and coils L1 and L4 resonate with the broadcast signals of the superbands, respectively, and the capacitors C1, C2 and coils L1 and L2, L4 and L5, respectively. A variable capacitance diode (VD1) (VD2) which resonates with the broadcast signal of the VHF high band and causes the capacitors C1, C2 and coils L1-L3, L4-L6 to resonate with the broadcast signal of the VHF low band, respectively. ), Coils L1, L4, coils L1, L2, L3, L4, and coils according to the superband, VHF highband, and VHF lowband selection signals SB (HB) (LB). Diodes D1 and D2 (D3 and D4) (D5) and capacitors (C3) and (C4) and (C5), which allow (L1-L3) and (L4-L6) to be inductively coupled, respectively.
이와같이 구성된 종래의 VHF밴드 전자동조 튜너는, 안테나(ANT)의 수신신호에서 방해파는 제거되고, VHF대역의 방송신호만 필터(1)를 통과하고, 증폭기(2)에서 증폭되어 고주파 동조회로(3)에 입력된다.In the conventional VHF band fully tuned tuner configured as described above, the interference wave is removed from the received signal of the antenna ANT, only the broadcast signal in the VHF band passes through the filter 1, and is amplified by the amplifier 2 so as to be a high frequency tuning circuit ( 3) is entered.
이와같은 상태에서 슈퍼밴드 선택신호(SB)가 입력될 경우네는 다이오드(D1)(D2)가 도통상태로 되고, 코일(L1)(L4)을 통과하는 고주파 신호가 다이오드(D1)(D2)를 통하고, 콘덴서(C3)를 통해 교류적으로 접지되며, 이때 등가회로는 제2도에 도시된 바와같이 되어 코일(L1)(L2)만 유도 결합된다.In this state, when the superband selection signal SB is input, the diodes D1 and D2 become conductive, and the high frequency signal passing through the coils L1 and L4 is the diodes D1 and D2. Through the capacitor (C3), AC is grounded, and the equivalent circuit is as shown in Figure 2, only the coil (L1) (L2) is inductively coupled.
궤러면 튜닝전압(TU)에 따라 가변용량 다이오드(VD1)(VD2)의 용량이 가변되면서 가변용량 다이오드(VD1)(VD2), 콘덴서(C1)(C2) 및 코일(L1)(L4)이 슈퍼밴드의 선택된 채널의 방송신호에 공진되므로 증폭기(2)의 출력신호에서 슈퍼밴드의 선택된 채널의 방송신호만 고주파 동조회로(3)를 통과하여 혼합기로 입력된다.When the capacitance of the variable capacitance diodes VD1 and VD2 varies according to the tuning voltage TU, the variable capacitance diodes VD1, VD2, capacitors C1, C2, and coils L1, L4 become supersized. Since it is resonant with the broadcast signal of the selected channel of the band, only the broadcast signal of the selected channel of the superband is passed through the high frequency tuning circuit 3 and input to the mixer from the output signal of the amplifier 2.
그리고 VHF하이밴드 선택신호(HB)가 입력될 경우에는 다이오드(D3,D4)가 도통상태로 되고, 코일(L1,L2)(L4,L5)을 통과하는 고주파 신호가 다이오드(D3,D4) 및 콘덴서(C4)를 통해 교류적으로 접지되며, 등가회로는 제3도에 도시된 바와같이 되어 코일(L1,L2)(L4,L5)이 유도 결합되며, 리액턴스가 증가하여 VHF 하이밴드로 동작하게 된다.When the VHF high band selection signal HB is input, the diodes D3 and D4 are in a conductive state, and the high frequency signals passing through the coils L1 and L2 and L4 and L5 are connected to the diodes D3 and D4. AC is grounded through capacitor C4, and the equivalent circuit is as shown in FIG. 3, and coils L1, L2 (L4, L5) are inductively coupled and reactance is increased to operate as a VHF high band. do.
그러면 튜닝전압(TU)에 따라 가변용량 다이오드(VD1)(VD2)의 용량이 가변되면서 가변용량 다이오드(VD1)(VD2), 콘덴서(C1)(C2) 및 코일(L1-L2) 및 코일(L1-L3)(L4-L6)이 VHF로우밴드의 선택된 채널의 방송신호에 공진되어 증폭기(2)의 출력신호에서 VHF로우밴드의 선택된 채널의 방송신호가 고주파 동조회로(3)를 통과 및 혼합기에 입력된다.Then, the capacitances of the variable capacitance diodes VD1 and VD2 vary according to the tuning voltage TU, and the variable capacitance diodes VD1 and VD2, the capacitors C1 and C2, and the coils L1 to L2 and the coils L1. -L3) (L4-L6) is resonant with the broadcast signal of the selected channel of the VHF low band so that the broadcast signal of the selected channel of the VHF low band passes through the high frequency tuning circuit 3 in the output signal of the amplifier 2 and the mixer. Is entered.
그러나 상기와 같은 종래의 고주파 동조회로는 슈퍼밴드, VHF하이밴드 및 VHF로우밴드의 동조회로가 직렬로 결합되어 있으므로 각 밴드의 동조시 각 밴드의 동조회로의 임피던스 차이 및 선택도의 차이에 의해 높은 주파수에 동조 또는 슈퍼밴드의 방송신호를 동조함에 따라 동조밴드폭이 넓게 되고, 이로 인하여 방해내성, 인접 채널의 방해내성 및 혼신등이 악화되었음은 물론 세계 각국의 전파방해 내성규정을 통과할 수 없었으며, VHF의 전체 대역을 3개의 밴드로 구분하여 작업성이 저하되고, 생산성이 낮을뿐만 아니라 각 동조회로간의 표유용량 및 임피던스 차이에 의해 VHF대역을 2개의 밴드로 구분할 경우에는 VHF대역 일부의 방송신호를 모두 수신하지 못하게 되는 등의 문제점이 있었다.However, in the conventional high frequency tuning circuit as described above, since the tuning circuits of the super band, the VHF high band, and the VHF low band are coupled in series, the high frequency tuning circuit has a high frequency due to the difference in impedance and selectivity of the tuning circuit of each band. Tuning band width is widened by tuning to frequency or broadcasting signal of super band, and this results in deterioration of interference resistance, interference resistance of adjacent channel and interference, and it is not able to pass radio interference immunity regulations of various countries. When the VHF band is divided into two bands by dividing the entire band of the VHF into three bands, the workability is lowered, and the productivity is low, and the stray capacitance and impedance difference between the tuning circuits is divided into two bands. There was a problem such as not receiving all the signals.
본 고안은 상기와 같은 종래의 제반 문제점들을 해결하기 위하여 안출한 것으로서, 40-470㎒의 VHF전체대역을 2개의 밴드로 구분하여 고주파 동조부를 각기 구성함으로써 각 밴드간의 임피던스 차이 및 표유용량에 의한 영향을 배제하고, 동조특성을 향상시켜 이미지 방해내성, 인접채널 방해내성을 향상시킴은 물론 광대역화를 이루고 생산성이 향상되도록 하는 고주파 동조회로를 제공하는데 목적이 있는 것으로 이를 첨부된 제4도 및 제5도의 도면을 참조하여 상세히 설명한다.The present invention has been devised to solve the above-mentioned problems, and the high frequency tuning part is formed by dividing the entire VHF band of 40-470MHz into two bands, thereby affecting the impedance difference between each band and the stray capacitance. 4 and 5, which are intended to provide high frequency tuning circuits for improving the image disturbance resistance and the adjacent channel disturbance resistance by improving the tuning characteristics and achieving broadband and improving productivity. It will be described in detail with reference to the drawings.
제4도는 본 고안의 고주파 동조회로도로서 이에 도시된 바와같이, 튜닝전압(TU)에 따라 슈퍼 밴드 및 VHF하이밴드의 선택된 채널의 방송신호에 동조되는 콘덴서(C11-C14), 코일(L11,L12) 및 가변용량 다이오드(VD11,VD12)로 된 하이밴드 동조부(11)와, 튜닝전압(TU)에 따라 VHF로우밴드의 선택된 채널의 방송신호에 동조되는 콘덴서(C15-C18), 코일(L13,L14) 및 가변용량 다이오드(VD13,VD14)로 된 로우밴드 동조부(12)와, 상기 하이밴드 동조부(11)에는 쵸크코일로 동작하고 로우밴드 동조부(12)에는 동조용 코일로 동작하는 코일(L15)과, 상기 코일(L15)을 통과한 고주파를 하이밴드 선택신호(HBV)에 따라 바이패스시켜 상기 로우밴드 동조부(12)에 입력되지 않도록 하는 다이오드(D11) 및 콘덴서(C19)와, 로우밴드 선택신호(LBV)에 따라 상기 로우밴드 동조부(12)에 쵸크코일로 동작하는 코일(L16)과, 하이밴드 및 로우밴드 선택신호(HBV)(LBV)에 따라 각기 도통되면서 하이밴드 및 로우밴드 동조부(11)(12)에서 동조된 방송신호를 혼합기로 출력하는 다이오드(D12)(D14)로 구성하였다.4 is a high-frequency tuning circuit diagram of the present invention, as shown therein, capacitors C11-C14 and coils L11, L12 tuned to the broadcast signals of selected channels of the super band and the VHF high band according to the tuning voltage TU. ) And a high band tuning section 11 consisting of variable capacitance diodes VD11 and VD12, and capacitors C15-C18 and coil L13 tuned to the broadcast signal of the selected channel of the VHF low band according to the tuning voltage TU. Low band tuning section 12 consisting of L14 and variable capacitance diodes (VD13, VD14), the high band tuning section 11 as a choke coil, and the low band tuning section 12 as a tuning coil A diode D11 and a capacitor C19 for bypassing the high frequency passing through the coil L15 and the high frequency passing through the coil L15 according to the high band selection signal HBV so as not to be input to the low band tuning unit 12. And a choke coil operated as a choke coil to the low band tuning section 12 according to the low band selection signal LBV. The diode D12 outputs a broadcast signal tuned by the high band and low band tuning units 11 and 12 to the mixer while conducting according to one L16 and the high band and low band selection signal HBV LBV. ) (D14).
이와같이 구성된 본 고안의 고주파 동조회로는 슈퍼밴드 및 VHF하이밴드 채널의 방송신호를 선택할 경우에 하이밴드 선택신호(HBV)에 의해 다이오드(D11)(D12)가 도통상태로 되고, 고주파 증폭기에서 코일(L15)을 통과한 VHF대역의 방송신호는 다이오드(D11) 및 콘덴서(C19)를 통해 접지로 바이패스되고, 로우밴드 동조부(12)의 입력단자도 다이오드(D11) 및 콘덴서(C19)를 통해 교류적으로 접지되므로 로우밴드 동조부(12)는 동작하지 않게 된다.In the high-frequency tuning circuit of the present invention configured as described above, the diodes D11 and D12 become conductive by the high-band selection signal HBV when the broadcast signals of the superband and VHF high-band channels are selected. The broadcast signal of the VHF band passing through L15 is bypassed to ground through the diode D11 and the capacitor C19, and the input terminal of the low band tuning unit 12 is also passed through the diode D11 and the capacitor C19. Since the ground is alternating current, the low band tuning section 12 is not operated.
그러므로 증폭기로부터 입력되는 방송신호중에서 튜닝전압(TU)에 따라 선택된 슈퍼밴드 및 VHF하이밴드채널의 방송신호가 하이밴드 동조부(11)에서 동조되고, 다이오드(D12)를 통해 혼합기로 출력되며, 이때 코일(L15)은 쵸크코일로 동작하여 고주파 특성이 개선되고, 로우밴드 동조부(12)에 의한 간섭이 없게 되어 제5도에 도시된 바와같이 선택도 특성이 개선되며, 종래에 비하여 광대역화가 된다.Therefore, among the broadcast signals input from the amplifier, the broadcast signals of the superband and VHF highband channels selected according to the tuning voltage TU are tuned by the highband tuning unit 11, and are output to the mixer through the diode D12. The coil L15 operates as a choke coil to improve the high frequency characteristic, and there is no interference by the low band tuning unit 12, so that the selectivity characteristic is improved as shown in FIG. .
그리고 VHF로우밴드의 방송신호를 선택할 경우에 로우밴드 선택신호(LBV)에 의해 다이오드(D13,D14)가 도통상태로 되고, 다이오드(D11,D12)는 차단상태로 되므로 하이밴드 동조부(11)에서 동조된 방송신호는 다이오드(D12)에 의해 차단된다.When the broadcast signal of the VHF low band is selected, the diodes D13 and D14 are turned on by the low band selection signal LBV, and the diodes D11 and D12 are turned off so that the high band tuning section 11 is selected. The broadcast signal tuned at is blocked by the diode D12.
그러므로 증폭기로부터 입력되는 방송신호는 코일(L15)을 통과하고, 튜닝전압(TU)에 따라 선택된 VHF로우밴드 채널의 방송신호가 다이오드(D14)를 통해 혼합기로 출력되며, 이때 코일(L15)은 로우밴드 동조용 코일로 동작하고, 코일(L16)은 쵸크코일로 동작하게 된다.Therefore, the broadcast signal input from the amplifier passes through the coil L15, and the broadcast signal of the VHF low band channel selected according to the tuning voltage TU is output through the diode D14 to the mixer, where the coil L15 is low. It operates as a band tuning coil, and the coil L16 operates as a choke coil.
이상에서 상세히 설명한 바와같이 본 고안은 40-470㎒의 VHF전체 대역을 2개의 밴드로 구분하여 고주파 동조부를 각기 구성함으로써 각 밴드간의 임피던스 차이 및 표유용량에 의한 영향을 배제하고, 동조특성을 향상시켜 이미지 방해내성, 인접채널 방해내성을 향상시킴은 물론 광대역화를 이루고 생산성이 향상되는 효과가 있다.As described in detail above, the present invention divides the entire VHF band of 40-470 MHz into two bands, and configures high-frequency tuning units to eliminate the influence of impedance differences and stray capacitance between the bands, and to improve tuning characteristics. As well as improving image disturbance resistance and adjacent channel interference resistance, broadband and productivity are improved.
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Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR2019910023751U KR940003083Y1 (en) | 1991-12-24 | 1991-12-24 | High frequency tunning circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR2019910023751U KR940003083Y1 (en) | 1991-12-24 | 1991-12-24 | High frequency tunning circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| KR930016677U KR930016677U (en) | 1993-07-29 |
| KR940003083Y1 true KR940003083Y1 (en) | 1994-05-12 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR2019910023751U KR940003083Y1 (en) | 1991-12-24 | 1991-12-24 | High frequency tunning circuit |
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| Country | Link |
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| KR (1) | KR940003083Y1 (en) |
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1991
- 1991-12-24 KR KR2019910023751U patent/KR940003083Y1/en not_active IP Right Cessation
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| KR930016677U (en) | 1993-07-29 |
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